Piston ring



July 24, 1928. 1,678,248

H. s. FRANK PISTON RING Filed Jan. 15, 1925 ATTORNEY lPetented July2l4, 19 28.

I ee).

isses. "FRAN-K, von.isnookmrnj EW YORK.

- Application filed January "This invention relates to piston rings.

One of the ohjeets of my inventionis the method or process of producing piston rings which will -'-expand laterally Within the pisston-ring groove. r V V s V "finother omect of my invent-ion is -to pro- Vlde Wring 'aCGOIHP llShIlngifhe results sought V hy the method.

groove endweanin'g down-not only o'f' the It is'u well known faet that when a pieton ringdoesmot properly fit thepiston ring groove the =eonstant hammering inotio'n hy the piston ring against the *piston groove wells will prutluzill-y result in wideningthe piston ring itself, but also of the piston, thereby causing :an exeess "of lubricant to penetrate above the piston. fl

This results in excessive car-hon deposits in the comhustion c'ha'mber and deficiency in the-engine operation, "not to speak *ot the cloggingof the spztrk plugs.

Toovereoine the so-cailletl *flop of the rings within the pistonjgrooves, -:many attempts have been niade to so construct the ring as to reduce its notion within thegrooves. In great many =oases the *ring was inside of a plurrlity of purtsincluding spring members,wedges, and other means designed to assure the proper fit of the ring Within its groove while r'eciprocajting with the piston. There :elso 'hrwe been provided various kinds o ffso-callledoil retaining grooves the ring designed to receive excessive oil and drain it below the piston. All these attempts how I ever, I seem to have been futile as they-effectedthe 'trueness ofthe ring. In 1 other 7 words th-e zittemptDf preventing the 011 from reachinguhowe the piston, resulted in "the deformzition of the ring body causing more undesirable eflects instead" of preventing them;

The present :methodend device is designed PISTON nine.

15, 1925, Serial no. 2380.

prevented from so-called flopping Within its groove.

The foregoing and further objects I inuention' yill be more fully apparent from the following description and the acconn panying drewings forming part of this disclosure andinwhlchf LFigurel represents one forin ofinyu-ing inplan view and;"elevation.

Figure 2 is another, modified "form' of my ring showing anfelevation and bottom viewthereofi i '1 Figure3 is'an enlarged nodified form ofa ring."

fFigures 4, 5, 657 8, and 9 are partialde tail views of modified'forins ofniyringt i detailed iew of a Referring to Figure 1 of the drfuwiugfh ring body 10 is shown Which ha-soverlapping ends 11 adapted to interengtge each other when the'ring is in operation. h At several places indicated at 12, the ring is slotted circum'ferenti ally{and at thepo'ints 13, radial'fcuts are provided whichcaus'e a separation of, the lower facial portioiisof the ring separated "by; slots '12. Thus afpltv ra-lity of resilient extensions 1'4 hireformed which arefadapted "to project below the lower face lfi of the ring. a

When new the faces of the ringhre subjeeted to the finishing operation which usually; comprises the grinding and olishing-0f the faces, the'upper face 16 will be uniform- 1y "finished, While the "finishing open'ettion ferent.

"The fork-like ien s 01- projections 14 of the lower face 15 will be somewhat will, when the -grindstonei's pressedover the lower ring face he depressedto a certain extent' 'intothe slotlQ, while the solid portions-{17" retained between each groove offprongs l l, "will; be uniformly "finished. Particularly the ends" nearest to slots 13 will beleajstsubjected to the finishing operation.

In-'oi'der to maintain the resilient quality of prongs '14, I preferthIysubjeCt the ring after the slotting operation to a hezttt'ree'tment adapted to change the molecular errangement of the ring material.

The process of'manufcture of thisring may be described. as followsz' First a ring blank is roughly machined, then slotted, Whereafter it iscompressed to assume a, natural ring-like shape and in this shape the ring is'aga-in'machin'ed at its inner i the ring is slotted peripherally and the'n' and outer surfaces and at its faces. Now

the radial cuts13 are provided. ,The'ribs or prongs 14 will now be flush with the solid portion of the ring. In order to make the prongs protrude beyond the solid portions of the slotted ring surface, two methods may be pressed into slots 12, and according'to. their the prongs are permanently set.

lengths will be more or less subjected to the grinding operation, the result being that they will extend beyond theface of the solid portions of the ring after the grinding o'pera-' tion. I The second way of bringing out the prongs beyond the surface is to insert intoslot's112 While the prongs of the ,ring

Spreaders. project beyond the face of the ring and are maintained in this positionthe ring is subjected to a high temperature, thenthe ring is permitted to slowly cool, while theprongs are still in their position projecting beyond the face of the ring. When the ring is cold ring may be refinished if desired.

- The prongs 14 now become veryresilient ing, while the rings are in operation j Referring 'to Figures 2 and 3 it willbe observed that the ring body 18 is'reduced at 19, and that the slots 20 are provided in the reduced body portion of the ring, whereby prongs 21 separated by radial slots 22 are offset relative to the ring body. 9

The reason for reducing the ring body and providing the prongs in the reduced portion thereof, may be explained as follows:

The prongs 21 not only project below the lower face 23 of the ring as seen in the upper part of Figure 2, but they also expand ra-- dially towards the outer surface of the ring as may be readily seen in the lower part of Figure 2.

Thus when no provision would be made for accommodating theradially or periphv erally projecting ends ofthe prongs, these ends would press against the cylinder wall and damage it by scorching it. These prongs may also break off duringhoperationp For these reasons it is preferable to offset the ring portion from which the prongs are formed. In rings of small diameter where it would be impracticable to provide long peripheral slots thereby gaining long resilient prongs, the double prong arrangement shown in Figures 1 and 2 is abandoned and i an arrangement shownin Figures 3 and 4 may be substituted.

Referring to Figure 3 there will be 'seen a ring body 24 which is reduced at 25, similar to the form described in Figure 2. The peripheral slots 26 are'made in the reduced Now the .howeverpreduction of the ring body is omitted. The ring body 29 is provided with plurality of peripheral slots 30 between which a solid portion 31 is retained. Radial slots32at the end of slots 30 separate the ring material to form prongs 33. P The way of producing the laterally ex+ panding prongs may. be simplified'by makmg oblique cuts from one surface of the ring towards'fthe otherl surface of the ring as shown for instanceinFigure 5 where the ring body, 34, having faces 35vand 36, is provided with oblique slots 37 directedfrom face 36 .towards face 35 thereby producing prongsfl38.. Slots 37 may be made either in straight line or on a curve.

Another representative'form is shown in Figure 6 where a ring body .39, having faces 40 and 41,"is provided with oblique curved slots 42" and 43 which are respectively directed from the surfaces 40 and 41 into the ring material. and sufficiently tough to prevent their breakring body 47 isillust-rated which is reduced at both ends 48 and 49 at which reducedends the prongs are formed in a similar manner as explained above. I I

a The upper; prongs 50 bear against the I uppergroove wall '51, while the lower prongs 52f bear against the lower grooves-wall 53. The original width or thickness of the ring is indicated at 54 and serves as spacer Within the grooves and prevents twisting of the ring which may be. caused by excessivecompression. For very-wide piston ring groovesa combination of twoor more piston rings of' my. design maybe employed as for instance shownin Figure 8 where an upper piston ring 55 with its prongs 56 is so arranged that v.its pronged face bears against the prongedface'of a lower. ring 57 provided with prongs58l 1 Thus the prongs of two rings bear against each other and press the unslotted' ring faces I against the piston ring groove. i In order to enhance the expansion qualities of the prongs in lateral direction there might be special springs provided which are made insertable into the ring slots.

In Figure 9 there is shown a modified form of a rin'gindicatedat 59 provided with prongs 60and separated from th'e'rin'g body 100 widerpistonring grooves. In this case a i by slot 61, in which is forced. a spring 62 bearing against the upper surface of the slot and against the inner prong surface, thereby increasing the tendency of the prongs to ex pand laterally.

While I have shown and described in the present application specific forms of my ring, and While I have mentioned a specific form of the process of making the ring, be it understood that changes c and improve ments may be made within the scope of my invention for which I claim f 1. A laterally expanding piston ring comprising a ring body having facial prongshaped resilient extensions expanding axially and radially outwards.

2. A laterally expanding piston ring, comprising a ring body reduced at least at one end and having facially projecting resilient extensions forming integral parts of the reduced portion of the ring body. y

3. A laterally expanding piston ring, comprising a ring body, reduced at least at one end and having prong-like portions forming integral parts of the reduced ring body and adapted to extend both laterally and peripherally.

Signed at New York in the county of New York and State of New York this 6th day of January, A. I). 1925.

HARRY s. FRANK. 

